The influence of guideline revisions on the process and outcome of hypertension management in general practice: a descriptive study.
BACKGROUND
Blood pressure does not reach guideline targets in the majority of hypertensive patients. Longitudinal data from general practice records on trends in hypertension management and the influence of guideline changes are lacking.


OBJECTIVE
To describe the longitudinal impact of guideline revisions on the process and outcome of hypertension management in a primary care based database.


METHODS
We extracted data from the Nijmegen Monitoring Project (NMP), an academic practice-based research network with 50,000 patients listed. Based on the years of publication of the first Dutch guideline on hypertension (1991) and two revisions (1997 and 2003), we formed three cohorts of patients newly diagnosed with hypertension. We compared data such as patient characteristics, 2-year blood pressure course, type of first-choice antihypertensive drugs, and number of medications after 2 years of treatment.


RESULTS
Both the mean age at time of diagnosis of hypertension and pulse pressure rose between cohorts. In agreement with revisions in the guidelines, the use of diuretics as first-choice drugs increased significantly from the first to the last cohort. The percentage of patients with three or more antihypertensive drugs remained equal. The relative 2-year systolic blood pressure decline did not differ with clinical relevance between the cohorts.


CONCLUSIONS
Our study has demonstrated that general practitioners achieve substantial and prolonged blood pressure reduction. However, guideline revisions do not seem to influence the amount of reduction, despite clear formulation of stricter treatment goals. In addition to qualitative research to identify the causes of this phenomenon, research to evaluate the effect of expert support systems on risk awareness and risk gain by additional treatment is necessary.
van der Wel
Mark
M
Department of General Practice, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands. m.vanderwel@hag.umcn.nl
Bakx
Carel
C
de Grauw
Wim
W
van Gerwen
Willem
W
Mulder
Jan
J
van Weel
Chris
C
D000367:Age Factors; D000959:Antihypertensive Agents / Q000627:therapeutic use; D015331:Cohort Studies; D003971:Diastole; D004363:Drug Utilization; D005194:Family Practice; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000188:drug therapy*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D017410:Practice Guidelines as Topic; D011787:Quality of Health Care; D012042:Registries; D013599:Systole
D000959:Antihypertensive Agents